1. Field of the Invention
This invention relates to a non-aqueous ink composition for inkjet.
2. Description of the Related Art
In recent years, a recording apparatus using an inkjet system is widely employed in various fields including not only at home but also in the office and other industrial applications. In the recording apparatus of inkjet system, an aqueous ink, a non-aqueous ink or a UV ink is employed depending on the purpose of use. Among these inks, although the aqueous ink is extensively employed because of its low cost and safety, the ink is accompanied with a problem that the ink cannot be quickly dried as it is applied to a high-speed printing. Moreover, when the aqueous ink is printed on plain paper (PPC paper), the paper is cockled subsequent to the drying of ink, thus generating so-called cockling. Since the UV ink can be quickly cured as soon as UV rays are irradiated, it is suited for use in the printing to non-absorptive media or in high-speed printing. However, it requires a UV irradiation device which is bulky and necessitates large power consumption.
Whereas, when the non-aqueous ink is employed for the printing on plain paper, the droplets of ink delivered from the inkjet head and impinged against a recording paper can be immediately penetrated into the recording paper within a short time. Therefore, the non-aqueous ink is applicable to high-speed printing without necessitating any particular mechanism, thus obtaining excellent printing images without generating cockling. Further, there has been proposed to use liquid paraffin (for example, (Moresco white P-40; Muramatsu Sekiyu Research Institute) as a solvent for the non-aqueous ink. Liquid paraffin is colorless, odorless, safe to human organism and hence suited for use as a solvent for the non-aqueous ink.